580 research outputs found
Pressure Effect and Specific Heat of RBa2Cu3Ox at Distinct Charge Carrier Concentrations: Possible Influence of Stripes
In YBa2Cu3Ox, distinct features are found in the pressure dependence of the
transition temperature, dTc/dp, and in DeltaCp*Tc, where DeltaCp is the jump in
the specific heat at Tc: dTc/dp becomes zero when DeltaCp*Tc is maximal,
whereas dTc/dp has a peak at lower oxygen contents where DeltaCp*Tc vanishes.
Substituting Nd for Y and doping with Ca leads to a shift of these specific
oxygen contents, since oxygen order and hole doping by Ca influences the hole
content nh in the CuO2 planes. Calculating nh from the parabolic Tc(nh)
behavior, the features coalesce for all samples at nh=0.11 and nh=0.175,
irrespective of substitution and doping. Hence, this behavior seems to reflect
an intrinsic property of the CuO2 planes. Analyzing our results we obtain
different mechanisms in three doping regions: Tc changes in the optimally doped
and overdoped region are mainly caused by charge transfer. In the slightly
underdoped region an increasing contribution to dTc/dp is obtained when well
ordered CuO chain fragments serve as pinning centers for stripes. This behavior
is supported by our results on Zn doped NdBa2Cu3Ox and is responsible for the
well known dTc/dp peak observed in YBa2Cu3Ox at x=6.7. Going to a hole content
below nh=0.11 our results point to a crossover from an underdoped
superconductor to a doped antiferromagnet, changing completely the physics of
these materials.Comment: 6 pages, 5 figures Proccedings of the 'Stripes 2000' Conference, Rome
(2000
RoboCup 2D Soccer Simulation League: Evaluation Challenges
We summarise the results of RoboCup 2D Soccer Simulation League in 2016
(Leipzig), including the main competition and the evaluation round. The
evaluation round held in Leipzig confirmed the strength of RoboCup-2015
champion (WrightEagle, i.e. WE2015) in the League, with only eventual finalists
of 2016 competition capable of defeating WE2015. An extended, post-Leipzig,
round-robin tournament which included the top 8 teams of 2016, as well as
WE2015, with over 1000 games played for each pair, placed WE2015 third behind
the champion team (Gliders2016) and the runner-up (HELIOS2016). This
establishes WE2015 as a stable benchmark for the 2D Simulation League. We then
contrast two ranking methods and suggest two options for future evaluation
challenges. The first one, "The Champions Simulation League", is proposed to
include 6 previous champions, directly competing against each other in a
round-robin tournament, with the view to systematically trace the advancements
in the League. The second proposal, "The Global Challenge", is aimed to
increase the realism of the environmental conditions during the simulated
games, by simulating specific features of different participating countries.Comment: 12 pages, RoboCup-2017, Nagoya, Japan, July 201
Nano-scale reservoir computing
This work describes preliminary steps towards nano-scale reservoir computing
using quantum dots. Our research has focused on the development of an
accumulator-based sensing system that reacts to changes in the environment, as
well as the development of a software simulation. The investigated systems
generate nonlinear responses to inputs that make them suitable for a physical
implementation of a neural network. This development will enable
miniaturisation of the neurons to the molecular level, leading to a range of
applications including monitoring of changes in materials or structures. The
system is based around the optical properties of quantum dots. The paper will
report on experimental work on systems using Cadmium Selenide (CdSe) quantum
dots and on the various methods to render the systems sensitive to pH, redox
potential or specific ion concentration. Once the quantum dot-based systems are
rendered sensitive to these triggers they can provide a distributed array that
can monitor and transmit information on changes within the material.Comment: 8 pages, 9 figures, accepted for publication in Nano Communication
Networks, http://www.journals.elsevier.com/nano-communication-networks/. An
earlier version was presented at the 3rd IEEE International Workshop on
Molecular and Nanoscale Communications (IEEE MoNaCom 2013
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